The generation of radio-frequency (RF) electromagnetic signals using optical-to-electronic conversion has been used to overcome limitations in electronic-based waveform generation techniques when high center frequencies and large percentage bandwidths are required. At present, these limitations become important for bandwidths greater than about 1 GHz. For applications in radar and communications systems, waveforms designed with specific radio frequency characteristics would be useful, for example, in conforming to regulatory requirements on spectral occupancy, optimally detecting specific radar targets, and compensating for the frequency-dependent characteristics of antenna systems, electronic components and the propagation media.